Miniature SAW duplexers with high power capability

Miniature SAW duplexers with high power capability corresponding to future GSM power regulation have been reported. We applied an improved cascade resonator structure to the duplexer in order to equalize power density on substrate. Power durability of the developed duplexers is verified by an experiment under the condition of 3/8 duty mode operation corresponding to future regulation. Furthermore, we reduce the coplanarity of the duplexer using a partial metalized patterning on the back of the base board. A 14.8/spl times/8.0/spl times/1.8 mm dimension structure and a 80 micron (80 micron improvement as compared with conventional structure) typical coplanarity is obtained for the duplexer.